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Via El Reg comes news that the International Linear Collider's Technical Design Report is finished, leaving only funding in the way of construction. From the article: "A five volume report containing the plans for the International Linear Collider has been handed over to the International Committee for Future Accelerators (ICFA) for approval. The Technical Design Report contains costings for the project, along with the design of the new collider. The new machine is significantly more powerful than the hoary European Large Hadron Collider and is likely to be sited in Japan, because the Pacific island nation has reportedly offered to pay for half of the construction costs. ... Jonathan Bagger, chair of the International Linear Collider Steering Committee, said the particle collider was 'ready to go.' 'The publication of the Technical Design Report represents a major accomplishment,' he continued. ... The ILC consists of two linear accelerators facing each other. "
A few years late, but hopefully not never.

Why build a super-expensive super-elaborate device, absolutely dependent on alignment and all that.. in a place where (1) land could hardly be less available or more expensive, (2) it tends to MOVE all the time (earthquakes, volcanoes, whatever), (3) it'll cost a bloody fortune for any visitors to visit.

Why not on some steppe somewhere, or a big flat desert (where there's at least sand for the concrete)?

Reminds me of how the LHC was supposed to be built in the US.. Then some politicians smelled pork, and fought over the location with complete disregard to the needs of the project until it became such a clustefuck the project was moved to Europe.

Progress delayed, scientific achievement and prestige denied to US academics.. All because some people wanted their pockets lined.

You seriously think the academics were more concerned about prestige than lined pockets?

You haven't met many academic scientists, have you? A long-term job at a major research institution pays enough for a comfortable, secure, upper-middle-class 1st-world lifestyle (and equally comfortable retirement), and most scientists are entirely content with that as long as their job description basically involves geeking out over obscure theory for days on end. If they wanted to line their pockets there are far better ways to do this - the people who really care about money figure out very early that staying in academia is not the most efficient way to get rich. (One of the scientists who used to work on the project I'm on ended up at Goldman Sachs.) But some academics will do pretty nearly anything short of murder for a Nobel prize if they smell an opportunity.

I've seen coworkers eventually bail from academia for greener pastures in terms of money, whether because they got tired of that particular ladder, or tired of the politics, or a change in priorities related to money. A few went into finance, some making a huge amount of money, and some not so much. But a lot of it was much more boring than that, and were able to go into industry jobs, sometimes only vaguely related to their research experience, and get free training and starting pay at least twice what t

That was to be the SSC, not the LHC, and the "politicians who smelled pork" was mainly Bush 1, who got it started in Texas in spite of the fact that if they built it at Fermilab a significant portion of the infrastructure would have already been in place.

The LHC was only ever proposed at CERN using the old LEP tunnel. The US had a proposal for the SSC which had a higher energy but lower luminosity (and so had effectively the same reach at the LHC). These were two entirely different machines. My understanding is that the SSC proposal sank because US politicians moved the location to Texas for political gain. Since Texas had none of the infrastructure that places like Fermilab had this essentially doubled the cost of the project and was partly the reason for it being cancelled...but I was still a grad student in Europe around that time so I had little direct knowledge of the politics.

However one of the fall outs from the cancellation is the reason why the ILC will not get built in the US. Too many physicists around the world got burnt by US political wrangling over which they had no input or control and their grant money quite literally ended up in the hole in the ground in Texas.

Japan is paying for half the fees because having it there would be beneficial to them for obvious reasons.Their government is willing to invest great quantities of money to bolster up their physics research sector.

Those devices are built deep underground, so there is no need to purchase that much land and effects of tectonic activity are minimal.

The Japanese have become pretty good at building stuff that is earthquake proof. I was in Tokyo when the 11/3 quake hit and there was really very little damage to buildings.

The problem with Fukushima was that it takes a long, long time for a reactor to shut down and the earthquake damaged the cooling system even before the tsunami got there. With a particle accelerator it shuts down pretty much instantly, and earthquakes take time to build up so in reality you have a few seconds for the auto-stop system to

Who said Japan is paying for half the fees? Physicists hope that Japan will stump up, but this has not been stated by anyone in authority to make such a decision. $5 bn is not small change.
Nb: asking for money may be awkward at the moment following an uncontrolled release of a tiny amount of radioactive material at JPARC a couple of weeks ago in somewhat uncomfortable circumstances...

Who said Japan is paying for half the fees? Physicists hope that Japan will stump up, but this has not been stated by anyone in authority to make such a decision. $5 bn is not small change.

Usually a nation hosting such a project pays for the infrastructures. And if you look at the costing (if I remember well from my PHD), it represents from 1/3 to 1/2 of the total cost : 40 km tunnel is quite expensive.
You are right in the sense that I'm not aware of any declaration of Japan concerning the amount of their participation, but in the end that is still about what they will have to pay

You took my thunder. You're points are all equally valid and on point. I don't get this either. With the Yen on the slide, kind of hard to understand where they came up with the will to pony up the cash. But ok, they did. I guess the prestige and visitor money it will bring in is worth it.

IANAP, but the Wiki article on linacs sez that the advantage of a linear accelerator is that you can use bigger, heavier ions since there's no need to continually accelerate them just to keep them in a circle. That energy is sometimes given off as synchrotron radiation, which would be wasted.

Another bonus: now that we know where to looking for the Higgs, we can make it for a lot less energy. The LHC needed extra power to make the Higgs in particular ways that left an easily-noticeable signal (in particle ph

Sorry you large English problem. Didn't we find the Higgs a few months ago?

A scientific discovery is not a binary issue. I'm not 100% convinced that the Higgs has been found, but I'm pretty sure some new physics was found, Higgs or not. We need to do more experiments in the same range to find out more about what it is we actually found, so to me the GP makes sense. (IAAP.)

Linacs are better because they can use singular particles (like electrons) as well, which means for 33% of the power, you can still achieve per-particle collision energies on the same sort of scale as the LHC (i.e. smash 2 electrons, rather then 2 balls of 3 quarks each).

Linacs are better because they can use singular particles (like electrons) as well

Circular accelerator can use electrons too, in fact there is plenty of accelerator which use different type of particules at the same time (most of the pre-accelerator of the LHC such as the PS and the SPS accelerate electron, positrons, protrons and heavy ions in a seconds timescale)

The collision energies are ~10 % of LHC's. The benefit of a linear collider is that leptons like electrons and positrons can be used, making the analysis of the collisions simpler.

The LHC's predecessor was the "Large Electron Positron" collider, so that's not a particular reason to use a linear accelerator.

Lepton accelerators do have an advantage over baryon colliders in that leptons are (as far as we can tell) indivisible; if you smash two leptons together with X amount of energy each, you get a collision of energy 2X. With baryons, the energy of each is mostly divided up between their three constituent quarks. Colliding two baryons usually results in a collision between one quark from each, so your collisions only use about 1/3 of the energy that was put in.

The LHC's predecessor was the "Large Electron Positron" collider, so that's not a particular reason to use a linear accelerator.

Yes the LEP was the predecessor of the LHC (in fact LHC is in the very same tunnel LEP was), but LEP was at much lower energy (120MeV) than the LHC (6TeV) or what would be the ILC (1TeV).
LEP was at the limit of the energy "reasonably" achievable for a circular lepton collider, because energy is lost by synchrotron radiation in circular accelerator.
The LHC as a hardron collider is not really affected by this, but to get to the energy of the ILC, an linear accelerator was needed.
The main paradigm in high e

A circular one would be preferable to a linear one when your goal is to reach as high a number of collisions as possible at your target energy (as it is here), because in a circular accelerator you can store the beams instead of having to produce and dump them continuously. But unfortunately a circular collider is not possible due to the enormous synchrotron radiation at the energies aimed for, which forces you among other things to continuously pump enormous amounts of energy in your beams.

Also as electron/positrons are primordial particles (not composed by other particles), when an collision occurs, the total energy of the electron/positron is used to make new particles.
On the other side, hardrons are composed by quarks and gluons, so when a hadron collides, as in reality it is one of the quarks which collides, the energy available for the collision is much lower than the hadron energy (and this energy is an unknown to be measured, which makes the analysis more difficult).

The one issue I'd have with locating it in Japan is, of course, earthquakes. This is going to be *how* long... and the alignment is how many zeros to the right of the decimal point? All of which would suggest frequent shutdowns to re-align, and that's assuming no *major* earthquakes.

The JPARC beam is a quite a bit lower in energy than the ILC and the accuracy tolerance is far, far larger than the ILC will require for collisions. Also the beam line will be packed with accelerator cavities, not bending magnets, and taking out those cavities to add magnets to go around a kink will reduce the beam energy - and not just by the lack of cavities but also by the synchrotron. None of this is really important for a proton accelerator.

Funding is generally the most important part, and when you leave it to last, it shows something about your management ability. Something about putting the cart before the horse comes to mind.

This how all the big science project I heard about works. If you wait a politician to say "I have a few billion left and I don't know what to do with it, let's make a kick ass science experiment !" you may wait for long long time....
Also politics don't know shit about science, (as they know nothing about technology in general), it would be the best way to get useless (in the sense not scientificly necessary) experiment to be built.

Just to be clear: the reason it's a linear collider and not circular is for synchrotron radiation losses.

The largest circular lepton collider was LEP (the Large Electron/Positron collider, formerly housed in the now-LHC tunnel) ran at 100GeV/beam. They lost about 2% of the beam energy every turn, which has to be replenished. If you tried to build a circular collider the same circumference as LEP, but run it at the ILC energy of 250GeV/beam, you'd lose about 30% of your energy on every turn. That's not sustainable.

You could argue that you can go to a bigger-diameter ring, but once you're above 30km circumference you'll have to dig more tunnel than for the ILC anyway, so you can't win. That's why it's a linear collider.